Vindex

Part of speech: noun

Definitions

1. A person who defends or protects others from harm or danger
2. Someone who acts to guard or shield someone or something from attack
3. An individual who stands up for or supports a cause or person to prevent harm

Etymology: Latin "vindex" was a legal and public term for a champion who stepped forward to defend someone, or to claim a person or property, in court. The word carried a sense of protection against wrong, and that is the thread that carried it into English as a noun for a defender against harm. The English word is a direct borrowing from Latin, so it kept the Roman courtroom flavour of its source rather than acquiring a later everyday sense. Its use is mostly literary and formal, which suits a term whose original job was to stand up publicly for someone who could not stand up for themselves.